US20020011050A1 - Suction cleaner with cyclonic dirt separation - Google Patents

Abstract

The invention relates to cyclonic dirt separator comprising a dirt-collection assembly including a dirt tank having an inlet aperture and an outlet aperture, a cyclonic separator, at least one filter element, and a suction source fluidly connected with the dirt collection assembly. In one embodiment, the cyclonic dirt separator includes a separator plate cooperating with the housing to form a toroidal region of the dirt tank for aiding in the separation of dirt from a suction airstream developed by the suction source. The separator plate has an outer diameter smaller than the inner diameter of the dirt tank, creating a gap between the outer edge of the separator plate and the inner wall of the dirt tank. A further embodiment includes dual cyclonic separators fluidly connected through a filter assembly. A further embodiment includes a cyclonic separator in the form of a tangential helical ramp.

Description

RELATED APPLICATIONS
• This application claims the benefit of U.S.[0001]Provisional Application 60/201,933, filed May 5, 2000 and U.S.Provisional Application 60/269,044, filed Feb. 15, 2001, all of which are incorporated herein in their entirety.
BACKGROUND OF THE INVENTION
• 1. Field of the Invention[0002]
• The invention relates to suction cleaners, and in particular to a separator for a suction cleaner. In one of its aspects, the invention relates to a separator with a cyclonic airflow path to separate dirt and debris from air drawn into the cleaner. In another of its aspects, the invention relates to a separator that deposits the dirt and debris in a collection receptacle. In another of its aspects, the invention relates to a separator including a supplementary fine particle filter.[0003]
• 2. Description of the Related Art[0004]
• Dirt separators for suction cleaners, using cyclonic action for separation of dirt from the airflow, are known. U.S. Pat. No. 4,944,780, issued Jul. 31, 1990, to Usmani, discloses a central vacuum system having a cylindrical dirt tank with an interior cylindrical wall adjacent to a tangential inlet. Dirt-laden air drawn into the tangential inlet circulates about the interior of the cylindrical tank to the outside of the interior cylindrical wall. Entrained particulates are separated from the airstream and drop to the bottom of the cylindrical dirt tank. Exhaust air, which may carry smaller particulates, is drawn through a pleated cylindrical filter that is carried on a spindle inside the interior cylindrical wall. Waste air that passes through the filter is drawn through an exhaust opening and is exhausted from the central vacuum cleaner through an exhaust outlet. U.S. Pat. No. 2,943,698, issued Jul. 5, 1968, to Bishop discloses a cylindrical dirt tank having a tangential air inlet, an interior frusto-conical shield, and a cylindrical filter element held in place by a frame comprising a cylindrical wire mesh or perforate screen. After dirt-laden air is introduced into the tank through the inlet, heavier dirt particles fall into a bottom portion of the dirt tank while waste air and any fine particles left in the waste air are exhausted through an air exhaust outlet. The filter element is interposed between the dirt tank and the air exhaust outlet to filter fine particles from the exhaust air.[0005]
SUMMARY OF THE INVENTION
• According to the invention, a vacuum cleaner comprises a housing defining a cyclonic airflow chamber for separating contaminants from a dirt-containing airstream, and a cyclonic chamber inlet and an airstream outlet in fluid communication with the cyclonic airflow chamber. A nozzle base includes a main suction opening fluidly connected with the cyclonic chamber inlet. An airstream suction source is fluidly connected to the main suction opening and to the cyclonic airflow chamber inlet for drawing dirt-containing air from the main suction opening and passing the dirt-containing air to the cyclonic airflow chamber, and selectively establishes and maintains a dirt-containing airstream from the main suction opening to the dirt-containing airstream inlet. A main filter assembly includes a filter element positioned centrally within the cyclonic airflow chamber for filtering residual contaminants from the dirt-containing airstream prior to exit of the airstream from the cyclonic airflow chamber. A dirt-collecting bin is beneath the main filter assembly within the housing, and a separator plate between the filter element and the dirt-collecting bin forms a toroidal chamber within the housing and separates the toroidal chamber from a dirt-collecting chamber.[0006]
• In a preferred embodiment, the separator plate is mounted to a lower portion of the filter element and extends radially from the filter element toward the housing. The separator plate forms a gap with the housing for passage of dirt particles from the toroidal chamber to the dirt-collecting bin. The gap between the separator plate and the housing is annular, the separator plate being circular and the housing having a circular wall adjacent the separator plate.[0007]
• In a preferred embodiment, the cyclonic chamber inlet is in the toroidal chamber.[0008]
• In a further embodiment, the airstream outlet is in an upper central portion of the housing.[0009]
• In a further embodiment, a secondary filter positioned between the filter element and the airstream outlet.[0010]
• In a further embodiment, the secondary filter comprises a fine mesh.[0011]
• In a further embodiment, the airstream outlet is in a lower portion of the housing.[0012]
• In a further embodiment, the relative cross-sectional area of the separator plate with respect to the housing is in the range of 0.75 to 0.95.[0013]
• In a further embodiment, the relative cross-sectional area of the separator plate with respect to the housing is in the range of 0.8 to 0.92.[0014]
• In a further embodiment, the relative cross-sectional area of the separator plate with respect to the housing is about 0.9.[0015]
• In a further embodiment according to the invention, a vacuum cleaner comprises a housing defining a first cyclonic airflow chamber for separating contaminants from a dirt-containing airstream, said housing further comprising an airstream inlet and an airstream outlet in fluid communication with said first cyclonic airflow chamber, a nozzle base including a main suction opening fluidly connected with said first cyclonic airflow chamber inlet, and an airstream suction source fluidly connected to the main suction opening and to the first cyclonic airflow chamber inlet for drawing the dirt-containing airstream from the main suction opening and passing the dirt-containing airstream to the first cyclonic airflow chamber. The suction source selectively establishes and maintains the dirt-containing airstream from the main suction opening to said first cyclonic airflow chamber. A second cyclonic airflow chamber is formed coaxially with the first cyclonic airflow chamber. A main filter assembly including a filter element is positioned between the first and second cyclonic airflow chambers for filtering residual contaminants from the dirt-containing airstream prior to exit of the airstream from the first cyclonic airflow chamber. A first dirt-collecting bin is beneath the first cyclonic airflow chamber and a second dirt-collecting bin in communication with the second cyclonic air flow chamber is positioned axially of the first dirt-collecting bin.[0016]
• In a further embodiment, a frusto-conical wall defines the second cyclonic airflow chamber and a wall of the second dirt-collecting bin.[0017]
• In a further embodiment, the second dirt-collecting bin is positioned axially above the first dirt-collecting bin.[0018]
• In a further embodiment, the airstream outlet is positioned in a lower portion of the housing. The airstream outlet is positioned concentrically with respect to the second cyclonic airflow chamber.[0019]
• In a further embodiment, the filter element is a foraminous wall.[0020]
• In a further embodiment, a separator plate is positioned between the first cyclonic airflow chamber and the first dirt-collecting bin. The relative cross-sectional area of the separator plate with respect to the housing is in the range of 0.75 to 0.95.[0021]
• In a further embodiment, at least one vane is positioned between the first and second cyclonic airflow chambers for imparting a tangential velocity component to the airflow.[0022]
• In a further embodiment according to the invention, a vacuum cleaner comprises a housing defining a cyclonic airflow chamber for separating contaminants from a dirt-containing airstream, and an airstream inlet and an airstream outlet in fluid communication with the cyclonic airflow chamber. A nozzle base includes a main suction opening fluidly connected with the cyclonic airflow chamber inlet. An airstream suction source is fluidly connected to the main suction opening and to the cyclonic airflow chamber inlet for drawing the dirt-containing airstream from the main suction opening and passing the dirt-containing airstream to the cyclonic airflow chamber. The main suction source selectively establishes and maintains the dirt-containing airstream from the main suction opening to the cyclonic airflow chamber inlet. A main filter assembly includes a filter element for filtering residual contaminants from the suction airstream. A dirt-collecting bin is beneath the cyclonic airflow chamber within the housing. The cyclonic airflow chamber is formed by a tangential helical ramp.[0023]
• In a further embodiment, the main filter assembly is concentric with cyclonic airflow chamber.[0024]
• In a further embodiment, there is an opening from the cyclonic airflow chamber into the dirt-collecting bin and an opening from the dirt-collecting bin into the main filter assembly whereby the airstream changes direction to enter the main filter assembly.[0025]
• In a further embodiment, the airstream outlet is centrally located within the housing. The airstream outlet passes through the dirt-collecting bin.[0026]
BRIEF DESCRIPTION OF THE DRAWINGS
• In the drawings:[0027]
• FIG. 1 is a front view of a suction cleaner housing with cyclonic dirt separation according to the invention.[0028]
• FIG. 2 is a side view of the suction cleaner of FIG. 1.[0029]
• FIG. 3 is a rear view of the suction cleaner of FIGS.[0030]1-2.
• FIG. 4 is an exploded perspective view of a dirt collection assembly of the suction cleaner of FIGS.[0031]1-3.
• FIG. 5 is an exploded perspective view of an upper housing and a motor housing of the suction cleaner of FIGS.[0032]1-3.
• FIG. 6 is a front view of a cylindrical separator of the suction cleaner of FIGS.[0033]1-5.
• FIG. 7 is a cross-sectional view through line[0034]7-7 of FIG. 6.
• FIG. 8 is a cross-sectional view taken through line[0035]8-8 of FIG. 2.
• FIG. 9 is a cross-sectional view taken through line[0036]9-9 of FIG. 2.
• FIG. 10 is a cut-away perspective view of the suction cleaner of FIGS.[0037]1-9 showing air flow around the cylindrical separator in the dirt collection assembly.
• FIG. 11 is a cut-away perspective view of the cylindrical separator of FIGS.[0038]1-10 showing an internal axial air flow.
• FIG. 12 is a cut-away perspective view of a further embodiment of a cyclonic separator for a suction cleaner according to the invention.[0039]
• FIG. 13 is a front cross-sectional view of the cyclonic separator of FIG. 12.[0040]
• FIG. 13A is a front cross-sectional view of a further embodiment of a cyclonic separator according to the invention.[0041]
• FIG. 14 is a cross-sectional view taken through line[0042]14-14 of FIG. 13.
• FIG. 15 is a cut-away perspective view of a further embodiment of a dirt collection assembly with cyclonic dirt separation according to the invention.[0043]
• FIG. 16 is an exploded perspective view of another embodiment of a dirt collection assembly with cyclonic dirt separation according to the invention.[0044]
• FIG. 17 is an enlarged perspective view of a filter assembly for the dirt collection assembly of FIG. 16.[0045]
• FIG. 18 is an enlarged perspective view of a cyclonic separator of the dirt collection assembly of FIG. 16.[0046]
• FIG. 19 is a plan view of the dirt collection assembly of FIG. 16.[0047]
• FIG. 20 is a cross-sectional view of the dirt collection assembly taken through line[0048]20-20 of FIG. 19.
DESCRIPTION OF THE PREFERRED EMBODIMENT
• With reference to FIGS.[0049]1-3, a suction cleaner withcyclonic dirt separation10 comprises anupper housing12, amotor housing14, and adirt collection assembly16. Theupper housing12 includes a two-piece handle18, anupper cord wrap20, and anair inlet22. Theupper housing12 further includes first andsecond switches36,38. Themotor housing14 includes alower cord wrap24, anexhaust air vent26 and afloor suction conduit28. Thedirt collection assembly16 comprises adirt tank30, atank cap32, and atank latch34. Each of thedirt collection assembly16,upper housing12, andmotor housing14 are configured to be assembled to present a smooth, continuous appearance, and to be generally fluid-tight.
• The[0050]dirt collection assembly16, as shown in FIG. 4, includes thedirt tank30, thetank cap32 and thetank latch34, and further includes acylindrical separator40, asecondary filter cup120, agasket58, aseparator plate42, a cylindricalpreliminary filter44, and atop plate46.Dirt tank30 includes anair inlet aperture31.Tank cap32 includestank latch recess33 for receivingtank latch34.Tank latch34 is an integral molding including abody portion96, two generally downwardly dependingleaf springs98, and two rearwardly extending catches100.Cylindrical separator40 is a hollow cylinder and includes in its interior radially inwardly projectingribs110, and on its exterior twist-and-lock grooves86.Secondary filter cup120 includes anupper rim122,cylindrical side wall124, andbottom wall126.Gasket58 is annular and resilient for forming a compressive seal.Separator plate42 is substantially annular, having anouter perimeter flange88, and further including an inner portion having upwardly extending separator plateradial ribs92 joined at a central hub and defining acentral cavity56, andseparator plate apertures94 defined radially betweenradial ribs92.Separator plate42 further includesfilter alignment slots85 adjacentradial ribs92.Separator plate42 further includes a dependingskirt95,skirt95 having inwardly projectingtabs84 for receipt in twist-and-lock grooves86.Preliminary filter44 includes afilter element48 in the form of a fine mesh screen, and upper and lower filter frames50,51.Lower filter frame51 includesalignment tabs53 for receipt inalignment slots85 ofseparator plate42.Top plate46 includes upwardly projectingstuds52 and a downwardly projecting frusto-conical portion54.Filter element48 has been found to be effective with a fine mesh having openings as small as 40 microns.
• Referring now to FIGS.[0051]6-7,ribs110 ofseparator40 each having anupper end112 slightly recessed from the upper end ofseparator40.Separator40 receivescup120 so thatribs110support rim122, suspendingcup120 withinseparator40,rim122 being substantially flush with the upper end ofseparator40.Separator plate42, withgasket58, is then received onseparator40 in a twist-and-lockarrangement using tabs84 andgrooves86, creating a sealing arrangement betweenplate42 andseparator40, and holdingcup120 in place againstribs110. Prior to placement ofplate42 onseparator40,preliminary filter44 is aligned onseparator plate42 using tabs andslots53,85, coaxial withcylindrical separator40. Frusto-conical section54 is configured to fillcentral cavity56 formed in theseparator plate42 to sandwichpreliminary filter44 therebetween.Preliminary filter44 is thereby sealingly received between thetop plate46 and theseparator plate42 when the frusto-conical section54 of thetop plate46 is received in thecentral cavity56 of theseparator plate42. Thepins52 projecting from thetop plate46 are received in recesses (not shown) on the underside of thetank cap32 for holding and aligning thetop plate46 to thetank cap32.
• Referring again to FIG. 4, and to FIG. 9, the[0052]dirt collection assembly16 comprisesdirt tank30 having a generally cylindrical interior, and having a central aperture76 on the bottom thereof. Thecylindrical separator40 is coaxially received within thedirt tank30, so that the open end of the hollowcylindrical separator40 is aligned with and sealingly engages the perimeter of the central aperture76 of thedirt tank30. Thecylindrical separator40 is preferably affixed totank30 at central aperture76, such as by welding. The assembly comprising thetank cap32,top plate46,preliminary filter44, andseparator plate42 are received within the upper end ofdirt tank30 asseparator plate42 is received on thecylindrical separator40 in the twist-and-lock arrangement of tabs andgrooves84,86. The perimeter of thetop plate46 includes a cantedlip82 configured to fit inside the upper edge of thetank30 in a sealing fit. Thetop plate46 is fixed within thetank cap32, so that when the top plate is fit within the top of thedirt tank30, the exterior of thetank cap32 aligns with the exterior of thedirt tank30 to provide a uniform flush surface. Theseparator plate42 includes aperimeter flange88 having a diameter less than the interior diameter of thedirt tank30, resulting in anannular gap90 between theseparator plate42 and the side walls of thedirt tank30.
• The[0053]motor housing14 havingexhaust air vent26, shown in FIG. 5, further comprises amotor cage60 havingexhaust vents68, a motor/impeller assembly62, animpeller gasket64 and amotor cover66. Motor/impeller assembly62 includes motor brushes63,impeller intake65, and motor electrical connections (not shown). Motor/impeller assembly62 is closely received withinmotor cage60,motor cage60 further comprising integral ribs (not shown) that cooperate with the exterior of motor/impeller assembly62 in a nesting relationship.Motor cover66 includes a raisedintake port70 havingapertures72.Gasket64 is configured to create a fluid seal betweenmotor cover66 and motor/impeller assembly62 so thatimpeller intake65 is in sealed fluid communication withintake port70.Motor cage60 andmotor cover66 are configured to enclose motor/impeller assembly62 andgasket64, providing sealed fluid communication between themotor cover66 andexhaust vents68, through motor/impeller assembly62.Motor housing14 is configured to mate with the bottom of theupper housing12 so that themotor cover66 sealingly fillscentral aperture74, and the bottom of theupper housing12 sealingly covers themotor housing14. Assembly of themotor cage60 within themotor housing14, and further assembly of themotor housing14 to theupper housing12, therefore creates a sealed fluid path between the interior of theupper housing12 atapertures72 of themotor cover66, to exhaustoutlet26 ofmotor housing14, through motor/impeller assembly62.
• Referring now to FIGS.[0054]8-11, thedirt collection assembly16 can be assembled and inserted into theupper housing12 so that thecylindrical separator40 within thetank30 is aligned with and fluidly connected with themotor cover66, and theinlet aperture31 of thedirt tank30 is further fluidly connected with theair inlet22, as particularly shown in FIGS. 8 and 10.Dirt collection assembly16 is held inupper housing12 bytank latch34 as will be further described below. Theair inlet22 is therefore fluidly connected to theexhaust air vent26 of themotor housing14 through theaperture31 of thedirt tank30, thepreliminary filter element44, theseparator plate42, the hollowcylindrical separator40, theapertures72 of the raisedportion70 of themotor cover66, themotor impeller assembly62, and theexhaust vent68 of themotor cage60.
• The user controls the suction cleaner by activating one of the[0055]switches36,38 to supply power to themotor impeller assembly62. When themotor impeller assembly62 is activated, a suction force is generated at themotor cover66, causing a flow of air from themotor cover66 through themotor impeller assembly62,motor cage60 and into themotor housing14, and then to atmosphere through theexhaust air vent26. A post-motor filter (not shown) is configured to fully occupy, and is inserted in, the space between exhaust vents68 andexhaust air vent26. When themotor cover66 is sealingly and fluidly connected to thecylindrical separator30, as in when thedirt collection assembly16 is fully installed in theupper housing12, the suction force is fluidly connected through thecylindrical separator30,separator plate42,preliminary filter44 andaperture31 to theair inlet22. A suction hose or nozzle of known construction is generally attached to theair inlet22 for use in cleaning a surface.
• As air is drawn into the[0056]air inlet22, theair inlet22 imparts a tangential component to the inlet air, as shown in FIG. 10, as it enters thedirt tank30 through theaperture31. The air enters thedirt tank30 in a toroidal section of the dirt tank formed betweentop plate46 andseparator plate42, and between thepreliminary filter44 and the interior tank wall. As the air flows in a tangential direction about thedirt tank30, heavier particles of dirt and debris are propelled outwardly by centrifugal force and fall under the force of gravity through thegap90 formed between theperimeter flange88 of theseparator plate42 and thedirt tank30 into the lower portion of thedirt tank30. It has been found thatseparator plate42 acts as a separator between two air velocity zones, one existing in thetoroidal chamber80 having a relatively high rotational air velocity, and a second zone separated from thetoroidal chamber80, belowseparator plate42, having a much lower rotational air velocity. The high rotational air velocity in thetoroidal chamber80 forces dirt particles contained in the airstream to the outside of the chamber where they will be drawn through thegap90 to the outside offlange88. As the airstream flows into the zone beneath theseparator plate42 and the air velocity decreases, the dirt particles will fall out of the airstream and collect and thedirt tank30. It has been found that narrowing thegap90, in the sense of having a high ratio of the surface area of theplate42 to the overall cross-sectional area of the housing, is beneficial to maintaining the two air velocity zones. This must be balanced with maintaining agap90 large enough to enable passage of larger dirt particles such as hair, carpet fuzz, etc. A relative plate surface area in the range of 0.75 to 0.95 with respect to the housing cross-sectional area is effective in defining the two air velocity zones while enabling the passage of large dirt particles, with the preferred ratio of surface areas being 0.8 to 0.92, or optimally 0.9.
• The air flow circulates tangentially about the interior of the[0057]tank30 until it is drawn inwardly toward thepreliminary filter element44, as shown in FIG. 11. As the air flow passes through thepreliminary filter element44, thefilter element44 prevents larger dirt particles and debris, that did not fall to the lower portion of thedirt tank30, from passing into the interior offilter element44 and then into the interior ofseparator40 andfilter cup120. The air is then drawn downwardly betweenseparator plate radials92 through separator plate apertures94 (see FIG. 8), throughfilter cup120 which traps additional finer particles, and passes axially through the hollow interior of thecylindrical separator40, then throughapertures72 and themotor housing14 to atmosphere through the post motor filter (not shown) and theexhaust air vent26.
• Dirt and debris, when collected in the[0058]dirt tank30, can be discarded by removing thedirt collection assembly16 from theupper housing12.Dirt collection assembly16 is retained inupper housing12, as stated above, bytank latch34 ontank cap32. Leaf springs98bias latch34 upwardly by pressing against the bottom ofrecess33, forcing thecatches100 underneath alip35 of thehandle18, thereby retaining thetank cap32 against thehandle18.Latch34 is released by depressing thelatch body96 against the biasing force of theleaf springs98, thereby releasing thecatches100 from thelip35. Thedirt collection assembly16 can then be tilted away from thehousing portion12. With thedirt collection assembly16 removed from theupper housing12, the assembly comprisingtank cap32,top plate46,preliminary filter44 andseparator plate42, can be removed fromdirt tank30 andcylindrical separator40 as a unit by counter-clockwise rotation of the twist-and-lock arrangement of tabs andgrooves84,86. The upper portion of thedirt tank30 and thefilter cup120 are thus open so that they can be emptied by a user.Filter cup120 can further be removed fromseparator40 for cleaning, andtop plate46 can be further separated from theseparator plate42 for cleaning or replacement of thepreliminary filter assembly44. Upon reassembly as described above,dirt collection assembly16 is replaced inupper housing12 by inserting the lower portion of theassembly16 into thehousing portion12 and tilting it inwardly untilcatches100 resiliently slide pastlip35 to bias upwardly and engagelip35 and holdassembly16 in place inupper housing12.
• Referring to FIG. 12, a further embodiment of a[0059]cyclonic dirt separator140 according to the invention comprises acylindrical cyclone chamber150 having anupper wall142 and asidewall144, thesidewall144 terminating in a lower offsetlip146. Anannular collar148 depends fromupper wall142, thecollar148 being centered in thecylindrical chamber150. Anexhaust outlet154 in theupper wall142 and within theannular collar148 is fluidly connected with a suction source (see FIG. 14).Sidewall144 further includes atangential air inlet152 aligned proximate theupper wall142 for generating a tangential airflow in thechamber150 parallel to theupper wall142.
• The[0060]cyclonic dirt separator140 further comprises aprimary filter element168. In a preferred embodiment, theprimary filter element168 comprises a cylindricalfine mesh screen170 retained by thecollar148 that depends fromupper wall142 of thechamber150.Cyclonic dirt separator140 further comprises aseparator plate158 in the form of a solid disc having an upstandingannular collar164. In the preferred embodiment, the upstandingannular collar164 is aligned with the dependingcollar148 of theupper wall142 so that thecylindrical screen170 is retained at the ends thereof by each of thecollars148,164. In this manner,separator plate158 is suspended fromupper wall142, forming atoroidal chamber180 between thecylindrical screen170 and thesidewall144, and between theupper wall142 and theseparator plate158, respectively. In the preferred embodiment,air inlet152 is vertically aligned betweenupper wall142 andseparator plate158 such that the tangential airflow generated fromtangential air inlet152 is directed into thetoroidal chamber180.
• With further reference to FIGS.[0061]13-14, the tangential airflow, containing particulate matter, passes throughtangential air inlet152 and intotoroidal chamber180 to travel around thecylindrical screen170. As the air travels about thetoroidal chamber180, heavier dirt particles are forced towardsidewall144. These particles will fall under the force of gravity through agap166 defined between anedge162 ofseparator plate158 and thesidewall144. Referring particularly to FIG. 13, dirt particles falling through thegap166 drop through theopen end156 ofchamber150 and are collected in thedirt cup160. The upper end ofdirt cup160 is received in a nesting relationship in lower offsetlip146 of thesidewall144 to seal thecyclone chamber150 to thedirt cup160.
• As the inlet air traverses through[0062]toroidal chamber180, casting dirt particles towardsidewall144, the inlet air will be drawn throughcylindrical screen170, throughexhaust outlet154, exhaust/suction conduit196, through a secondary (pre-motor)filter192 to thesuction source190. Thesecondary filter192 removes additional particulate matter from the exhaust airstreams prior to the airstreams being drawn through thesuction source190. Apost-motor filter194 can also be provided downstream of thesuction source190 to remove additional fine particulate matter from the exhaust airstream before it is released to the atmosphere.
• [0063]Dirt cup160 is removably connected tochamber150. Accumulated dirt can be discarded by axially displacingdirt cup160 fromcyclone chamber150 so that it disengages from offsetlip146.Dirt cup160 can then be removed fromchamber150 to discard accumulated dirt.
• A further embodiment of a[0064]cyclonic separator440 is shown in FIG. 13A. thecyclonic separator440 comprises acylindrical cyclone chamber450 having anupper wall442 and asidewall444, thesidewall444 terminating in a lower offsetlip446. A substantiallycylindrical filter assembly468 depends fromupper wall442, being centered in thecylindrical chamber450. Anexhaust outlet454 in theupper wall442 and within thefilter assembly468 is fluidly connected with asuction source490.Sidewall444 firther includes atangential air inlet452 aligned proximate theupper wall442 for generating a tangential airflow in thechamber450 parallel to theupper wall442.
• In a preferred embodiment, the[0065]filter assembly468 comprises a plurality ofapertures470 passing through the wall of theassembly468 and fluidly connectingair inlet452 withexhaust outlet454.Cyclonic dirt separator440 further comprises aseparator plate458 in the form of a solid disc.Separator plate458 is secured byfasteners472 to a lower end ofcylindrical filter assembly468, parallel toupper wall442, forming atoroidal chamber480 between thecylindrical filter assembly468 and thesidewall444, and between theupper wall442 and theseparator plate458, respectively. In the preferred embodiment,air inlet452 is vertically aligned betweenupper wall442 andseparator plate458 such that the tangential airflow generated fromtangential air inlet452 is directed into thetoroidal chamber480.
• As in the previous embodiment, the tangential airflow, containing particulate matter, passes through[0066]tangential air inlet452 and intotoroidal chamber480 to travel around thecylindrical filter assembly468. As the air travels about thetoroidal chamber480, heavier dirt particles are forced towardsidewall444. These particles will fall under the force of gravity through agap466 defined between anedge462 ofseparator plate458 and thesidewall444. Dirt particles falling through thegap466 drop through theopen end456 ofchamber450 and are collected in thedirt cup460. The upper end ofdirt cup460 is received in a nesting relationship in lower offsetlip446 of thesidewall444 to seal thecyclone chamber450 to thedirt cup460.
• As the inlet air traverses through[0067]toroidal chamber480, casting dirt particles towardsidewall444, the inlet air will be drawn through theapertures470 incylindrical filter assembly468, throughexhaust outlet454, exhaust/suction conduit496, through a secondary (pre-motor)filter492 to thesuction source490. Thesecondary filter492 removes additional particulate matter from the exhaust airstreams prior to the airstreams being drawn through thesuction source490. Apost-motor filter494 can also be provided downstream of thesuction source490 to remove additional fine particulate matter from the exhaust airstream before it is released to the atmosphere.
• [0068]Dirt cup460 is removably connected tochamber450. Accumulated dirt can be discarded by axially displacingdirt cup460 fromcyclone chamber450 so that it disengages from offsetlip446.Dirt cup460 can then be removed fromchamber450 to discard accumulated dirt.
• A further embodiment of a cyclonic separator[0069]300 is depicted in FIG. 15. The cyclonic separator300 comprises adirt bin310 having a cylindrical configuration with anexterior wall312, abottom wall314 having acentral opening316 integral with a hollowcylindrical shaft318 extending frombottom wall314.Shaft318 includes anupper end320 and extends coaxially withinbin310 so thatupper end320 extends above anupper end322 ofexterior wall312 ofdirt bin310.Dirt bin310 firther comprises atangential inlet opening324 passing through theexterior wall312 of thedirt bin310, located proximate theupper end322 of theexterior wall312 of thedirt bin310.
• The cyclonic separator[0070]300 further comprises acyclonic insert330 having a substantially hollowcylindrical body332,cylindrical body332 shown as having aneck portion334 in a central area thereof, so that the diameter of thecylindrical body332 is slightly narrower atneck portion334.Cylindrical body332 is further contemplated as being uniform in diameter, i.e. eliminatingneck portion334.Cyclonic insert330 further comprises anannular bottom portion336.
• Annular[0071]bottom portion336 includes acentral opening338 configured to closely conform to the exterior of thecentral shaft318 of thedirt bin310.Bottom portion336 is connected to the exterior wall of thecylindrical portion332 of thecyclonic insert330, and further includes aseparator flange340.Separator flange340 extends downwardly at an obtuse angle beyond the exterior wall of thecylindrical body332.
• The[0072]cylindrical body332 of thecyclonic insert330 has a diameter less than the diameter of thecylindrical dirt bin310, so that when thecyclonic insert330 is inserted into thedirt bin310, atoroidal portion342 is formed therebetween. Theseparator flange340 does not extend tocylindrical wall312, leaving agap344 between theseparator flange340 and the interior of thecylindrical wall312 of thedirt bin310.
• The interior of the[0073]dirt bin310 is thus divided into twotoroidal portions342,346, the firsttoroidal portion342 being between thecyclonic insert330 and thewall312 of thedirt bin310, and the secondtoroidal portion346 formed between thecentral shaft318 and thecylindrical wall312 of thedirt bin310, beneath theseparator flange340.
• The[0074]cyclonic insert330 further comprises an upperannular flange portion348 integrally formed with thecylindrical body332 of thecyclonic insert330, theflange portion348 having an outer diameter equivalent to the outer diameter of thedirt bin310 and configured to be received in an engaging and sealing manner on theupper edge322 of theexterior wall312 of thedirt bin310.
• The[0075]cylindrical body332 of thecyclonic insert330 further comprises two wall portions, an imperviousupper wall portion352 and alower wall portion354 having a plurality ofperforations356 passing therethrough.Perforations356 are contemplated as being of uniform size and spacing, or of being arranged in a non-uniform pattern of varying apertures, as required to develop the most advantageous airflow pattern.
• The[0076]cyclonic insert330 further includes a plurality ofcanted vanes358 arranged in a ring about the interior of thecyclonic insert330 at thenecked portion334 of thecylindrical body332. Thevanes358 include acentral opening360 configured to closely receive thecentral shaft318 of thedirt bin310.
• The[0077]necked portion334, and thevanes358, substantially divide the volume between thecyclonic insert330 and thecentral shaft318 of thedirt bin310 into twotoroidal portions362,364. The firsttoroidal portion362 is bounded on its interior by thecentral shaft318 of thedirt bin310, and on its exterior by theperforated section354 of the cylindrical portion of thedirt bin310. The secondtoroidal portion364 is bounded on its interior by thecentral shaft318 of thedirt bin310 and on its exterior by thesolid portion352 of the cylindrical portion of thecyclonic insert330. the secondtoroidal portion364 is bounded at its lower end by thevanes358 and at its upper end by a frusto-conical chamber368 defined by a frusto-conical wall376.
• The cyclonic separator[0078]300 further comprises asecondary cyclone chamber370, thechamber370 comprising an outercylindrical wall372, a lowerannular wall374 and frusto-conical wall376. Thebottom wall374 of thechamber370 has anannular perimeter378 for abutting theperimeter edge350 of thecyclone insert330 to present a flush appearance and to resist removal of thechamber370 from theinsert330.
• The[0079]chamber370 further comprises achamber cap380, being a disk having a dependingrim382 for receipt in anupper portion384 of thecylindrical chamber370 in a sealing manner. Theexterior wall372,lower wall374 and frusto-conical wall376 of thechamber370 are integrally formed, forming a substantiallytoroidal receptacle386. The frusto-conical wall376 is shorter than theexterior walls372 of thechamber370 resulting in agap388 between atop edge390 of the hollow frusto-conical wall376 and thelid380 of thechamber370.
• Prior to assembly, therefore, the cyclonic separator[0080]300 comprises acylindrical dirt bin310 having a concentriccylindrical shaft314 passing from anaperture316 and aflat bottom314 to above theupper edge322 of thedirt bin310, forming a single toroidal chamber therebetween. Inserting thecyclonic insert330 in a sealing engagement with theupper edge322 of thedirt bin310 divides the interior of thedirt bin310 into twotoroidal portion342,346 to the outside of theinsert330. Thetoroidal portions342,346 are separated by theseparator flange340 of thecyclonic insert330, except for agap344 betweenseparator flange340 andwall312.
• The interior of the[0081]insert330 is divided intotoroidal sections362,364 inside thecylindrical body332 of theinsert330. Thetoroidal sections362,364 are defined by thevanes358. Thecentral shaft318 still projects above the top322 of thebin310 and theupper flange348 of thecyclonic insert330.
• Attaching the[0082]secondary cyclone chamber370 and itslid380 places theupper end320 of thecentral shaft318 within the hollow frusto-conical wall376 of thesecondary cyclone chamber370. The cyclonic separator300 is now sealed from the atmosphere except for thetangential inlet324 of thedirt bin310 and thecentral outlet316 at thebase314 of thedirt bin310. Thetangential inlet324 andoutlet316 are fluidly connected through thedirt bin310,perforations356 of thecyclonic insert330, through thetoroidal sections362,364 within thecyclonic insert330 and through theupper end320 of thecentral shaft318.
• The cyclonic separator, when used in a suction cleaner, will have a vacuum source fluidly connected to the[0083]outlet opening316, thereby forming a vacuum within the cyclonic separator300 and at thetangential inlet324 to thedirt bin310.Inlet324 will be fluidly connected to a surface cleaning apparatus. Dirt-laden air will be drawn through theinlet324 into the firsttoroidal section342, the air flow having a tangential component due to the orientation ofinlet324. As the dirt-laden air is circulated about the perimeter of thedirt bin310, the dirt will be driven toward theouter wall312 ofdirt bin310 and tend to fall towards thebottom wall314 to the outside of theseparator flange340.
• As the air circulates about[0084]dirt bin310, the air will be drawn inwardly toward theperforations356 in thelower portion354 of thecylindrical portion332 of thecyclonic insert330. Heavier particles of dirt will fall to the bottom of the dirt bin. Theseparator flange340 acts to discourage dirt particles from being recirculated in the air flow adjacent theperforations356.
• The air passing through the[0085]perforations356 continues to carry finer particulates that were not heavy enough to be deposited in the bottom of thedirt bin310. Theperforations356 substantially pass perpendicularly through thesurface354 of thecyclonic insert330 to further encourage deflection of dirt particles from the perforations and thereby removing them from the airflow.
• As the air flow passes through the[0086]perforations356, it begins traveling essentially along the outside of thecentral shaft318. It is been found that this air flow still maintains some rotational velocity. In the embodiment shown in FIG. 15, the airflow will strikevanes358.Vanes358 will increase the rotational velocity component to the air flow. The air flow in the uppertoroidal portion364 will therefore have a tangential component to encourage additional cyclonic action in thetoroidal section364.
• As the air flow travels to the frusto-[0087]conical chamber368, the rotational velocity of the air flow will increase, driving dirt particles toward the frusto-conical wall376 of thesecondary cyclone chamber370. In addition, the axial velocity components will push the dirt particles to thetop opening390. The tangential component will then direct the dirt particles to the outer secondarycyclonic chamber370, through thegap388. With very little airflow in the outer chamber of the secondarycyclonic chamber370, the velocity of the dirt particles drops dramatically and the dirt particles fall to thebottom386 of the secondarycyclonic chamber370.
• The remaining airflow, and those particles not having sufficient centripetal energy to be driven to the outside of the frusto-[0088]conical wall376, will be drawn through thetop end320 of thecentral shaft316, to be drawn to the vacuum source fluidly connected to theoutlet opening316. A fine particulate filter (not shown) is inserted in the exhaust airstream to remove those fine particulates not extracted by the cyclonic separator.
• An additional embodiment of a[0089]cyclonic separator200 for a suction cleaner is shown in FIGS.16-20.Cyclonic separator200 comprises adirt bin202, acyclonic housing204, first and second filter frames208,212, first and second filter seals206,214,filter medium210, and filterchamber lid216.
• The[0090]dirt bin202 is cylindrical in configuration, having anouter wall220, abottom wall222 having acentral opening224, and a centralcylindrical shaft226 encompassing theaperture224, thecylindrical shaft226 being concentric with theouter wall220 of thedirt bin202. Thecentral shaft226 has anupper end228 substantially even with anupper end230 of the dirt binouter wall220. The dirt bin thereby comprises a toroidal receptacle encompassed by theouter wall220 and thecentral shaft226, and by the dirt binlower surface222 and theupper edges228,230 of thecentral shaft226 andouter wall220.
• The[0091]cyclone housing204 is cylindrical, having an exterior diameter equal to the diameter of thedirt bin202. Thecyclone housing204 comprises a centralcylindrical filter chamber240 having anouter wall242, the diameter of thecylindrical filter chamber240 being smaller than the exterior diameter of thecyclone housing204, but concentric therewith. The annular region defined between theouter wall242 of thefilter chamber240 and the outer wall of thecyclone housing204 comprises aspiral channel250.Channel250 begins at anupper portion252 of thecyclone housing204 with aninlet opening254. Thechannel250 then follows the perimeter of the cyclone housing in a downward spiral fashion to achannel outlet256 on a lower portion of thecyclone housing204.
• The upper portion of the[0092]filter chamber240 comprises afilter chamber opening258. A lower portion of thefilter chamber240 comprises acentral opening260, anannular filter seat262 surrounding thecentral opening260 on the lower portion of thefilter chamber240, and an annularperforated inlet section264. Theannular filter seat262 is bounded on its interior and exterior edges by a raisedrim266, each raised rim being annular and perpendicular to the base of thefilter chamber240.
• The[0093]filter chamber lid216 is a flat disc having a diameter slightly greater than the diameter of thecylindrical filter chamber240, and having anannular depending rim268 inset from the edge oflid216 and adapted to be closely received within theopening258 offilter chamber240.Filter chamber lid216 further comprises two additional dependingannular rims270 each having a diameter corresponding to one of therims266 surrounding theannular filter seat262 in the lower portion of thefilter chamber240. Therims270 bound anannular filter seat272, theannular filter seat272 being centered on the underside of the circularfilter chamber lid216 for alignment with thefilter seat262.
• The first and second filter frames[0094]208,212 are identical in construction. The filter frames208,212 comprise a flatannular mating surface280 including a pair ofpin projections282 and a pair of pin receiving openings284 evenly spaced about the perimeter of themating surface280 so that thepins282 of the first filter frame can be received in the openings284 of the second filter frame, and vice versa, so that the mating surfaces280 of the first and second filter frames208,212 can abut in a flush manner.
• Referring to the[0095]first filter frame208 for the purpose of describing the construction of the filter frames208,212, thefirst filter frame208 further comprises a number ofribs286 depending from themating surface280 of thefilter frame208 in a slightly splayed manner, being substantially perpendicular to the plane of themating surface280 but canted slightly away from this center line of thefilter frame208. Theribs286 terminate in anannular base290. Based290 comprises an innerannular rim288 and anannular ring292 with a raisedouter rim294. The raisedouter rim294, thering292 and therim288 form a shallowannular cavity296 for receiving a lower portion of thefilter medium210. Each of the filter frames208,212 further comprises anannular recess298 on a face opposite themating surface280, therecess298 configured to receiveannular filter seal206,214.
• The[0096]filter medium210 is a hollow cylindrical arrangement of a pleated filter paper, the hollow cylinder having a diameter and wall thickness substantially corresponding to the width of theannular ring292 of thefilter frame208. Thefilter medium210 has a height substantially equal to the distance between theannular rings292 of the first and second filter frames208,212 when theframes208,212 are assembled with theirrespective mating surfaces280 in abutment.
• The[0097]cyclone separator200 is assembled by placing thecyclone housing204 in a sealing engagement with theupper end230 of thedirt bin202. The outer wall of thecyclone housing204 aligns with theouter wall220 of thedirt bin202, and theupper end228 of thecentral shaft226 sealing engages thecentral opening260 of thecyclone housing204.
• The filter frame is assembled by placing a[0098]first filter seal206 in theannular recess298 of thefirst filter frame208, placing the hollowcylindrical filter medium210 over thefirst filter frame208 so that the lower portion of thefilter medium210 is received in theannular recess296 of thefirst filter frame208, then inserting thesecond filter frame212 into thefilter medium210 until themating surface280 of thesecond filter frame212 abuts themating surface280 of thefirst filter frame208 in a flush manner. The upper portion of thefilter medium210 is thus received in theannular recess296 of thesecond filter frame212. The second filter seal is then placed in theannular recess298 of thesecond filter frame212.
• The filter assembly is then placed into the[0099]cyclone housing204 so that the annular base of thefirst filter frame208 is received in theannular filter seat262 of thecyclone housing204. Thefilter chamber lid216 can then be placed over the filter chamber opening258 so that the dependingrim268 resides immediately inside thefilter chamber wall242, and the annular base of thesecond filter frame212 can be received in theannular filter seat272 of thefilter chamber lid216 between therims270.
• The assembled cyclonic separator is now fluidly sealed from the atmosphere except for the inlet opening[0100]254 of thespiral channel250, and theoutlet opening224 at the base of thedirt bin202. Theinlet opening254 andoutlet opening224 are fluidly connected through thespiral channel250 into the interior of thedirt bin202 and then through theannular inlet section264 into thefilter chamber240. Any fluid flow must then pass through thefilter medium210 to reach thecentral opening260 at the base of thefilter chamber240, from whence it travels through thecentral shaft226 to theoutlet opening224.
• In a suction cleaner, the suction source is applied to the[0101]outlet opening224, thereby drawing a vacuum throughout the fluid path just described and theinlet opening254 is then directed by known structures to a surface or object to be cleaned, thereby drawing dirt laden air into the cyclonic separator. The tangential flow through thespiral channel250 will reduce the velocity in the particles in the air, causing them to fall under gravity into the toroidal dirt chamber of thedirt bin202. The air flow is further subjected to a severe change in direction as it must flow upwardly through theannular inlet section264 of thefilter chamber240 before it can pass through thefilter medium210 to theexhaust outlet224.
• While the invention has been specifically described in connection with certain specific embodiments thereof, it is to be understood that this is by way of illustration and not of limitation. Reasonable variation and modification are possible within the forgoing disclosure and drawings without departing from the spirit of the invention which is defined in the appended claims.[0102]

Claims (40)

What is claimed is:

1. A vacuum cleaner comprising:

a housing defining a cyclonic airflow chamber for separating contaminants from a dirt-containing airstream, said housing further comprising a cyclonic chamber inlet and an airstream outlet in fluid communication with said cyclonic airflow chamber;

a nozzle base including a main suction opening, said main suction opening being fluidly connected with said cyclonic chamber inlet;

an airstream suction source fluidly connected to said main suction opening and to the cyclonic airflow chamber for transporting dirt-containing air from the main suction opening to the cyclonic airflow chamber, said suction source selectively establishing and maintaining a dirt-containing airstream from said main suction opening to said cyclonic chamber inlet;

a main filter assembly including a filter element positioned centrally within said cyclonic airflow chamber for filtering residual contaminants from said dirt-containing airstream prior to exit of said airstream from said cyclonic airflow chamber;

a dirt-collecting bin beneath the main filter assembly within the housing; and

a separator plate between the filter element and the dirt-collecting bin and forming a toroidal chamber within the housing and separating the toroidal chamber from a dirt-collecting chamber.

2. A vacuum cleaner according toclaim 1 wherein the separator plate is mounted to a lower portion of the filter element and extends radially from the filter element toward the housing.

3. A vacuum cleaner according toclaim 2 wherein the separator plate forms a gap with the housing for passage of dirt particles from the toroidal chamber to the dirtcollecting bin.

4. A vacuum cleaner according toclaim 4 wherein the gap between the separator plate and the housing is annular.

5. A vacuum cleaner according toclaim 4 wherein the separator plate is circular and the housing has a circular wall adjacent the separator plate.

6. A vacuum cleaner according toclaim 2 wherein the separator plate is circular and the housing has a circular wall adjacent the separator plate.

7. A vacuum cleaner according toclaim 1 wherein the cyclonic chamber inlet is in the toroidal chamber.

8. A vacuum cleaner according toclaim 1 wherein the airstream outlet is in an upper central portion of the housing.

9. A vacuum cleaner according toclaim 8, further comprising a secondary filter positioned between the filter element and the airstream outlet.

10. A vacuum cleaner according toclaim 9 wherein the secondary filter comprises a fine mesh.

11. A vacuum cleaner according toclaim 1, further comprising a secondary filter positioned between the filter element and the airstream outlet.

12. A vacuum cleaner according toclaim 1 wherein the secondary filter comprises a fine mesh.

13. A vacuum cleaner according toclaim 1 wherein the airstream outlet is in a lower portion of the housing.

14. A vacuum cleaner according toclaim 1 wherein the relative cross-sectional area of the separator plate with respect to the housing is in the range of 0.75 to 0.95.

15. A vacuum cleaner according toclaim 1 wherein the relative cross-sectional area of the separator plate with respect to the housing is in the range of 0.8 to 0.92.

16. A vacuum cleaner according toclaim 1 wherein the relative cross-sectional area of the separator plate with respect to the housing is about 0.9.

17. A vacuum cleaner according toclaim 1 wherein the filter element comprises a fine mesh.

18. A vacuum cleaner comprising:

a housing defining a first cyclonic airflow chamber for separating contaminants from a dirt-containing airstream, said housing further comprising an airstream inlet and an airstream outlet in fluid communication with said first cyclonic airflow chamber;

a nozzle base including a main suction opening, said main suction opening being fluidly connected with said airstream inlet;

an airstream suction source fluidly connected to said main suction opening and to the first cyclonic airflow chamber for transporting the dirt-containing airstream from the main suction opening to the first cyclonic airflow chamber, said suction source selectively establishing and maintaining the dirt-containing airstream from said main suction opening to said first cyclonic airflow chamber;

a second cyclonic airflow chamber formed coaxially with the first cyclonic airflow chamber;

a main filter assembly including a filter element positioned between the first and second cyclonic airflow chambers for filtering residual contaminants from said dirt-containing airstream prior to exit of said airstream from said first cyclonic airflow chamber;

a first dirt-collecting bin beneath said first cyclonic airflow chamber; and

a second dirt-collecting bin in communication with the second cyclonic air flow chamber and positioned axially of the first dirt-collecting bin.

19. A vacuum cleaner according toclaim 18, further comprising a frustoconical wall defining the second cyclonic airflow chamber and a wall of the second dirtcollecting bin.

20. A vacuum cleaner according toclaim 19 wherein the second dirtcollecting bin is positioned axially above the first dirt-collecting bin.

21. A vacuum cleaner according toclaim 19 wherein the airstream outlet is positioned in a lower portion of the housing.

22. A vacuum cleaner according toclaim 19 wherein the airstream outlet is positioned concentrically with respect to the second cyclonic airflow chamber.

23. A vacuum cleaner according toclaim 22 wherein the second dirtcollecting bin is positioned axially above the first dirt-collecting bin.

24. A vacuum cleaner according toclaim 22 wherein the airstream outlet is positioned in a lower portion of the housing.

25. A vacuum cleaner according toclaim 18 wherein the airstream outlet is positioned concentrically with respect to the second cyclonic airflow chamber.

26. A vacuum cleaner according toclaim 25 wherein the second dirtcollecting bin is positioned axially above the first dirt-collecting bin.

27. A vacuum cleaner according toclaim 25 wherein the airstream outlet is positioned in a lower portion of the housing.

28. A vacuum cleaner according toclaim 18 wherein the filter element is a foraminous wall.

29. A vacuum cleaner according toclaim 18 wherein the second dirtcollecting bin is positioned axially above the first dirt-collecting bin.

30. A vacuum cleaner according toclaim 18 wherein the airstream outlet is positioned in a lower portion of the housing.

31. A vacuum cleaner according toclaim 18, further comprising a separator plate between the first cyclonic airflow chamber and the first dirt-collecting bin.

32. A vacuum cleaner according toclaim 31 wherein the relative cross-sectional area of the separator plate with respect to the housing is in the range of 0.75 to 0.95.

33. A vacuum cleaner according toclaim 31 wherein the relative cross-sectional area of the separator plate with respect to the housing is in the range of 0.8 to 0.92.

34. A vacuum cleaner according toclaim 31 wherein the relative cross-sectional area of the separator plate with respect to the housing is about 0.9.

35. A vacuum cleaner according toclaim 18, further comprising at least one vane positioned between the first and second cyclonic airflow chambers for imparting a tangential velocity component to the airflow.

36. A vacuum cleaner comprising:

a housing defining a cyclonic airflow chamber for separating contaminants from a dirt-containing airstream, said housing further comprising an airstream inlet and an airstream outlet in fluid communication with said cyclonic airflow chamber;

a nozzle base including a main suction opening, said main suction opening being fluidly connected with said airstream inlet;

an airstream suction source fluidly connected to said main suction opening and to the cyclonic airflow chamber for transporting the dirt-containing airstream from the main suction opening to the cyclonic airflow chamber, said suction source selectively establishing and maintaining the dirt-containing airstream from said main suction opening to said airstream inlet;

a main filter assembly including a filter element for filtering residual contaminants from said suction airstream; and

a dirt-collecting bin beneath the cyclonic airflow chamber within the housing,

wherein the cyclonic airflow chamber is formed by a tangential helical ramp.

37. A vacuum cleaner according toclaim 36 wherein the main filter assembly is concentric with the cyclonic airflow chamber.

38. A vacuum cleaner according toclaim 36, further comprising an opening from the cyclonic airflow chamber into the dirt-collecting bin and an opening from the dirt-collecting bin into the main filter assembly, whereby the dirt-containing airstream changes direction to enter the main filter assembly.

39. A vacuum cleaner according toclaim 36 wherein the airstream outlet is centrally located within the housing.

40. A vacuum cleaner according toclaim 36 wherein the airstream outlet passes through the dirt-collecting bin.

Images